The present application is related to the field of vehicle systems and, more particularly, to a vehicle control system and related methods.
Vehicle security systems are widely used to deter vehicle theft, prevent theft of valuables from a vehicle, deter vandalism, and to protect vehicle owners and occupants. A typical automobile security system, for example, includes a central processor or controller connected to a plurality of vehicle sensors. The sensors, for example, may detect opening of the trunk, hood, doors, windows, and also movement of the vehicle or within the vehicle. Ultrasonic and microwave motion detectors, vibration sensors, sound discriminators, differential pressure sensors, and switches may be used as sensors. In addition, radar sensors may be used to monitor the area proximate the vehicle.
The controller typically operates to give an alarm indication in the event of triggering of a vehicle sensor. The alarm indication may typically be a flashing of the lights and/or the sounding of the vehicle horn or a siren. In addition, the vehicle fuel supply and/or ignition power may be selectively disabled based upon an alarm condition.
A typical security system also includes a receiver associated with the controller that cooperates with one or more remote transmitters typically carried by the user as disclosed, for example, in U.S. Pat. No. 4,383,242 to Sassover et al. and U.S. Pat. No. 5,146,215 to Drori. The remote transmitter may be used to arm and disarm the vehicle security system or provide other remote control features from a predetermined range away from the vehicle. Also related to remote control of a vehicle function U.S. Pat. No. 5,252,966 to Lambropoulous et al. discloses a remote keyless entry system for a vehicle. The keyless entry system permits the user to remotely open the vehicle doors or open the vehicle trunk using a small handheld transmitter.
A relatively new development in the field of vehicle security relates to a transponder adapted to be carried by the vehicle user, such as on a key ring. The transponder is uniquely coded and this code must be received by a transponder reader at the vehicle, such as to permit vehicle starting. The reader includes a transmitter for temporarily charging a capacitor in the transponder so that the transponder can then transmit its unique code. The transponder requires no batteries, is relatively small, and can be sealed to avoid damage from moisture.
The transponder feature means that a would-be thief can no longer break the ignition switch housing to start the vehicle. Instead possession of the properly coded transponder is required or the vehicle will not start. Some variations of the transponder technology can eliminate the need for the traditional mechanical key altogether. A number of manufacturers offer such transponder and reader systems including Texas Instruments of Dallas, Tex. under the designation TIRIS. U.S. Pat. No. 5,905,444 to Zimmer and U.S. Pat. No. 5,897,598 to Puetz disclose further developments in the vehicle transponder security area.
Unfortunately, the majority of vehicle security systems need to be directly connected by wires to individual vehicle devices, such as the vehicle horn or door switches of the vehicle. In other words, a conventional vehicle security system is hardwired to various vehicle components, typically by splicing into vehicle wiring harnesses or via interposing T-harnesses and connectors. Connecting to a vehicle which includes a transponder reader and engine control circuit is further complicated. Moreover, another difficulty is that vehicle manufacturers discourage cutting and splicing into existing wiring to install aftermarket components. For example, a vehicle manufacturer may void a warranty for such activity.
In view of the foregoing background, it is therefore an object of the present invention to provide a vehicle control system and related method including additional control and/or security features in a vehicle that includes a transponder security feature.
It is another object of the present invention to provide a vehicle control system and related method that permits a simple interface of a vehicle security system into a vehicle including a transponder security feature.
These and other objects, features and advantages in accordance with the present invention are provided by a vehicle control system comprising a radio transponder to be carried by a user, a radio transponder reader at the vehicle for enabling at least one vehicle function based upon receiving a desired radio signal from the radio transponder when positioned in proximity therewith, and a jammer radio transmitter at the vehicle. The jammer radio transmitter selectively prevents the radio transponder reader from receiving the desired radio signal from the radio transponder, such as in response to control signals from a controller. The controller may be an alarm controller of a vehicle security system, especially an after-market security system where it is desired not to cut or splice into existing wiring.
The controller may comprise a receiver for receiving remotely generated signals to operate the jammer radio transmitter. The control system may also include a remote transmitter for generating control signals to be received by the receiver of the controller. For example, the remote transmitter may be a portable transmitter carried by the user, or may be a satellite, cellular or paging transmitter remote from the vehicle. An anti-hijack switch may also activate the jammer radio transmitter.
The at least one vehicle function in one embodiment is operation of a vehicle engine. In another embodiment, the at least one vehicle function may be permitting access through a vehicle door, that is, control of the door locks. In other words, the radio transponder may be positioned adjacent a door to unlock the doors, or may enable engine starting when positioned within the vehicle.
The control system may include at least one vehicle sensor, and the controller may activate the jammer radio transmitter responsive to the at least one vehicle sensor. Accordingly, the jammer radio transmitter is not powered until the transponder is about to be used, thus conserving vehicle battery power. For example, the vehicle security sensor may be a vehicle proximity sensor, a door or door lock position sensor, or an ignition switch sensor. Of course, an alarm controller is advantageously connected to various vehicle sensors for its traditional security monitoring functions.
The radio transponder may preferably be a passive radio transponder. Accordingly, the radio transponder reader may include a powering radio transmitter for powering the passive radio transponder.
The jammer radio transmitter may operate in several ways. For example, it may generate a noise signal to block successful reception of the desired radio signal from the radio transponder. In embodiments where the transponder generates a uniquely coded desired radio signal, the jammer radio transmitter may generate an incorrect code to block successful reception of the uniquely coded desired radio signal.
A method aspect of the invention is for vehicle control and preferably comprises the steps of: using a radio transponder reader at the vehicle to selectively enable at least one vehicle function based upon receiving a desired radio signal from a radio transponder when positioned in proximity, and selectively operating a jammer radio transmitter at the vehicle for preventing the radio transponder reader from receiving the desired radio signal from the radio transponder. The selective jamming may be responsive to jammer control signals. A receiver, such as part of an alarm controller, may be used for receiving remotely generated jammer control signals. The jammer radio transmitter may also be operated in response to an anti-hijack switch at the vehicle. The at least one vehicle function may be operation of a vehicle engine, or permitting access through a vehicle door, for example.